Author Topic: Molex wire connectors aren't tight  (Read 1440 times)

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Offline hoosier122Topic starter

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Molex wire connectors aren't tight
« on: July 25, 2010, 02:00:59 AM »
So I followed the tutorial on using molex connectors. (http://www.societyofrobots.com/electronics_wire_connector.shtml) But for some reason some of the connectors loosen over time.

Has anyone else run into this problem? My half-butt solution was to slightly bend the male connectors outward, but I was just wondering if there was a better solution to keep them tight.

***To clarify the pins that connect the wire to the molex are fine, it's when I connect the molex to male pins sticking out of my board that I get loose connections. I don't want to glue them, because that defeats the purpose of having connections in the first place.***

Thanks,

Chris
« Last Edit: July 25, 2010, 02:04:22 AM by hoosier122 »

Offline voyager2

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Re: Molex wire connectors aren't tight
« Reply #1 on: July 25, 2010, 02:34:57 AM »
Well you can super glue the metal parts of the connector to the plastic case.
Shouldn't effect the join between the connector and board, just means you can't change the wire out for another one.
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Offline dunk

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Re: Molex wire connectors aren't tight
« Reply #2 on: July 25, 2010, 04:03:45 AM »
are your male headers the right thickness for your female connectors?
(check the datasheet for your female connector pins.)
if the male is too thick it bends the female rather than just moving the "spring".


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Offline hoosier122Topic starter

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Re: Molex wire connectors aren't tight
« Reply #3 on: July 25, 2010, 10:38:55 AM »
are your male headers the right thickness for your female connectors?
(check the datasheet for your female connector pins.)
if the male is too thick it bends the female rather than just moving the "spring".


dunk.

I don't have the original packaging, but if I connect a molex connector and a male header and hold it upside down (no wires, just the connector) the molex connector does slide off. I swear I bought them as a set though.
« Last Edit: July 25, 2010, 10:40:24 AM by hoosier122 »

Offline amando96

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Re: Molex wire connectors aren't tight
« Reply #4 on: July 25, 2010, 10:42:12 AM »
You have to insert it very deep in the plastic thing, are the wires crimped correctly?
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Offline hoosier122Topic starter

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Re: Molex wire connectors aren't tight
« Reply #5 on: July 25, 2010, 05:55:48 PM »
You have to insert it very deep in the plastic thing, are the wires crimped correctly?

I assume so.?.?.? Why do the metal connectors put pressure on the header pin when they are connected properly?

The metal connector is flush with the end of the molex piece. Should the wire's insulation actually go into the molex connector?

Offline Webbot

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Re: Molex wire connectors aren't tight
« Reply #6 on: July 25, 2010, 06:04:00 PM »
Looking at the metal pin (before use) then it will normally have two x V shaped bits. When you insert the wire for crimping then the outermost V should hold onto the wire insulation, whilst the second V should hold onto the bare wire. (Well thats how I do it!).

So once finished and inserted into the housing, then 'Yes' the insulation should go down into the plastic outer housing. Otherwise you risk shorting bare wires between the neighboring pins in the same connector. And if these are the battery and ground then you risk shorting out the battery!

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Offline hoosier122Topic starter

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Re: Molex wire connectors aren't tight
« Reply #7 on: July 25, 2010, 06:13:04 PM »
Looking at the metal pin (before use) then it will normally have two x V shaped bits. When you insert the wire for crimping then the outermost V should hold onto the wire insulation, whilst the second V should hold onto the bare wire. (Well thats how I do it!).

So once finished and inserted into the housing, then 'Yes' the insulation should go down into the plastic outer housing. Otherwise you risk shorting bare wires between the neighboring pins in the same connector. And if these are the battery and ground then you risk shorting out the battery!



If I test the resistance at the battery and at the pins, in a perfect world I should have 0 loss, but what is an acceptable range of loss? 0~.05 Ohm?
« Last Edit: July 25, 2010, 06:15:29 PM by hoosier122 »

Offline amando96

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Re: Molex wire connectors aren't tight
« Reply #8 on: July 25, 2010, 07:34:25 PM »
The whole metal pin should be inside the plastic molex thing and slide in there without friction(that's what she said? :P )
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Offline hoosier122Topic starter

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Re: Molex wire connectors aren't tight
« Reply #9 on: July 25, 2010, 08:59:25 PM »
The whole metal pin should be inside the plastic molex thing and slide in there without friction(that's what she said? :P )

It is. I think the metal connectors  may not be square anymore (after crimping).

 


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